The present disclosure pertains to aqueous pigment dispersions based on polyurethane dispersants having heterocyclic functionalities capable of interacting with cellulose. These dispersions may be used to prepare aqueous inkjet inks, paints, and the like.
Dispersion methods are commonly used to disperse particles. A variety of dispersion processes have been described for using polyurethane dispersants for dispersing particles. Often the components used for the polyurethane dispersants are chosen to optimize the stability of the pigment dispersion, rather than to optimize the utility of the pigment dispersions.
Alternatively, the polyurethane dispersants can be optimized to improve the performance of the pigments dispersed with these dispersants. For instance, components may be chosen for the polyurethane dispersants to improve pigmented ink performance. For inkjet inks with polyurethane dispersed pigments, components may be chosen to optimize the print performance of inkjet inks.
U.S. patent application publication Nos. 20080264298 and 20070100023 disclose dispersants capable of interacting with calcium components present in many types of paper.
There has been effort in the art directed at improving color saturation of images from inkjet printing. As the inkjet industry moves to page-wide array printing, the requirements for repeating jetting cycles may be an order of magnitude higher than the traditional Small Office/Home Office market. These and other emerging needs require inks with improved color saturation. The present disclosure satisfies this need by providing pigment dispersions based on polyurethane dispersants having functionalities capable of interacting with cellulose.